Many vehicle control systems can benefit from an accurate estimation of the vehicle mass. Vehicle mass can change based on cargo and number of passengers. Vehicle mass may be affected by the attachment of a trailer to the vehicle. A vehicle mass estimation may be particularly useful for cargo carrying vehicles such as trucks and vans. Vehicle mass estimation is also useful for passenger vehicles in which the number of passengers may change during a trip. Better control can be achieved when vehicle mass is known. For example, systems such as powertrain and braking can provide more accurate control when vehicle mass is accurately known. As a result, safety and performance may be improved.
Vehicle stopping distance can be greatly affected by vehicle mass. A heavily loaded vehicle will have a longer stopping distance for a given applied braking force than an unloaded vehicle. A useful application for a vehicle mass estimation algorithm may be in a collision warning or avoidance system. A collision warning or avoidance system may calculate the stopping distance between the vehicle and an obstacle in the vehicle's path. The stopping distance is affected by the vehicle mass. Accurate estimation of the vehicle mass can improve the safety and performance of such systems.